Tundra Voles have the northernmost distribution of any North American species of Microtus. They are widespread in northern latitudes in Eurasia, too, where they are known as Root Voles, and probably migrated to North America across the Bering land-bridge during the Pleistocene. They prefer moist meadow habitats, particularly near lakes, streams, and marshes. Tundra Voles are active year-round. In the fall, they store food—grass seeds and other plant materials—for winter. Many northern predators depend on this species, including weasels, Wolverines, Arctic Foxes, falcons, gulls, and owls.

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Mammal Species of the World